Dialogue systems, for example spoken dialogue systems (SDSs) are used in many applications, including automated call centres, assistive technology, speech-driven or text-driven interactive mobile applications, speech or text interface for wearable devices and human-robot interactions for example, and are intended to interact with humans, for example to verbally interact with humans.
Dialogue systems may use pre-defined domain-specific ontologies and a policy model trained to work in the specific pre-defined domain. Multi-domain dialogue systems may switch between pre-defined domain ontologies and corresponding dialogue policies, using topic trackers to identify the pre-defined domain that most closely matches the input.
There is a continuing need to make dialogue systems operable across multiple domains, whilst reducing the training, maintenance and human design input needed for such systems.